1. Field
The present invention relates to an electrostatic image-developing toner, an electrostatic image developer, and a toner cartridge.
2. Description of the Related Art
A method for visualizing image information, such as electrophotographic method, is utilized in various fields at present. In the electrophotographic method, an electrostatic image is formed as image information on the surface of an image holding member by charging and electrostatic image formation. Thereafter, a toner image is formed on the image holding member surface by using a developer containing a toner, and the toner image is transferred onto a recording medium and then fixed on the recording medium. Through these steps, the image information is visualized as an image.
For example, JP-A-2006-337902 (the term “JP-A” as used herein means an “unexamined published Japanese patent application”) discloses “an electrostatic image-developing toner containing at least a binder resin, a coloring agent and a release agent, wherein the release agent is a hydrocarbon-based wax having a melting point of 50 to 100° C., a plurality of dispersed particles of the release agent are present in the toner, the number average particle diameter of dispersed particles in the toner is from 0.5 μm to 2.0 μm as measured by a binder resin dissolution method, the standard deviation is from 0.05 to 0.5, and the shape factor SF-1 of dispersed particles of the release agent is from 1.0 to 1.4”.
For example, JP-A-2004-145243 describes “a dry toner where wax is encapsulated as a particle in the toner, the wax is present throughout the toner from near the surface to the inside, and the concentration of wax present near the surface of the toner is larger than the concentration of wax present in the inside”. It is also disclosed in JP-A-2004-145243 to use “an eccentricity control resin having both a moiety close to the polarity of the binder resin and a moiety close to the polarity of the release agent, in a kneading pulverization production method”.
JP-A-2011-158758 describes “a toner where the content of wax is from 3.0 parts by mass to 20.0 parts by mass per 100 parts by mass of the binder resin and the degree of wax eccentricity in the depth direction of the toner is controlled”. It is also disclosed in JP-A-2011-158758 to arrange the wax at a position near the surface by controlling the hydrophilicity/hydrophobicity difference between the binder resin and the wax dissolved in a solvent”.
JP-A-2005-173208 describes a toner comprising at least a binder resin, a colorant, a wax, and hydrophobic titanium oxide particles, wherein the toner shows a peak temperature of a maximum endothermic peak ranging from 50 to 100° C. in the temperature range of from 30 to 150° C. in an endothermic curve by the differential scanning calorimetry (DSC); and the hydrophobic titanium oxide particles are subjected to a surface treatment with at least a silicone oil or a silicone varnish and shows an intensity ratio (Ia/Ib) of a maximum intensity Ia to a minimum intensity Ib in the X-ray diffraction in the range of from 20.0 to 40.0° in terms of 2θ satisfying a relation of (5.0≦Ia/Ib≦12.0).
In addition, JP-A-2005-107427 describes a toner comprising at least a resin, a colorant, a release agent, and inorganic particles, wherein at least the inorganic particles include two or more kinds of titanium oxides; one of the titanium oxides has an anatase type crystal form, and the other has a rutile type crystal form; one of the titanium oxides has a number average particle diameter Da of more than 20 nm and 60 nm or less, and the other has a number average particle diameter Db of 40 nm or more and 100 nm or less; and a relation of (Da<Db) is satisfied.